1. Technical Field of the Invention
This invention most generally relates to soap dispensers, and more particularly to disposable soap containers used in soap dispensers.
2. Background Art
The art of provisioning restrooms with liquid soap in such quantities as to provide a useful servicing interval, with the convenience of metered dispensing and disposable containers, has led to many solutions.
One is the use of disposable, integrated container/pump systems such as plastic bottles with pumps incorporated into their caps, which are disposed of when empty and replaced with all new units, or simply opened and refilled from a bulk source such as a larger bottle or container.
Another one is the use of wall-mounted dispensers which provide a greater degree of security and reliability for public-use and business-use restrooms. This type of unit is typically stocked by means of inserting a disposable, container of liquid soap into a cavity sized for the purpose within the upper region of the dispenser. This discussion proceeds in the context of this type of dispenser.
The soap container used in this type of dispenser is commonly comprised of a collapsible plastic bag inside a formed paperboard box, where the box is matched to the size of dispenser's container cavity. As supplied, the bag is filled with soap to the extent that it conforms to the interior dimensions of the box. The system is sometimes referred to as a bag-in-a-box. The uniform shape of the box is convenient for shipping and storage, and provides form to the heavy, full bag when it is placed in a dispenser cavity which might not otherwise provide adequate support to the collapsible bag alone.
A pump tube is attached to the bottom of the bag and engaged in the dispenser mechanism. The liquid soap is passed in metered amounts through this tube and expelled into the user's palm by activation of a push or pull lever which squeezes the tube against a backplate. The bag is airtight, so that as the soap is drawn from the bag, it gradually collapses within the box into a small knot of plastic.
The dispenser may be equipped with a small window in the cover looking into the soap container cavity. The box is typically supplied with a perforated slot on the front side, the slot covering material of which is removed at the time of insertion into the dispenser, allowing the tube to be extended downward into the dispenser mechanism, and the plastic bag to be viewed through the window when the dispenser is closed.
When the bag is totally or nearly depleted, as may be observed through the window, the dispenser is due to be serviced. This simply entails opening the dispenser, removing the empty container and installing a new one.
Dispenser cavities are generally designed to accept a specific, maximum size box, which defines the maximum volume or capacity of soap that the dispenser can hold. 500, 1000, and 1200 milliliter are some of the common sizes.
Occasionally in the course of design evolution, a dispenser design is modified in some fashion to gain an additional benefit such as a larger cavity which will accept a larger box of soap, thus providing the user with greater capacity per dispenser. When a given design change is released to production, several thousands of that design are likely to be produced and placed into permanent use in the industry before another design change is made.
Once installed, any shortcomings of a particular design not seriously affecting or fatal to its continuing use are generally tolerated by the user, as long as soap is supplied in compatible containers at reasonable prices.
Referring here to the prior art FIGS. 1--5, in one instance a manufacturer produced a variation of an earlier design which resulted in a dispenser cavity that is not optimal. Hinge structure on the inside of the cover plate of the dispenser closes into the lower front corners of the cavity volume, space otherwise available for a box of the same width and depth as the cavity, thereby restricting the maximum box and bag size that may be used in this dispenser.
In order to properly position a sufficiently narrow 1000 ml box-in-a-bag container in the remaining space available and to hold the box centered over the pump recess in the lower portion of the dispenser, the manufacturer modified the cavity by adding horizontal strakes to both sidewalls.
The problem with this design compromise is that several thousands of these dispensers have been installed over the years, all restricted to using the narrow 1000 ml box. Newer dispenser designs of the same general size as the subject prior art dispenser, can utilize 1200 ml containers. The ability to utilize larger soap containers without having to purchase and install new dispensers would provide a valuable service to these users. Neither the manufacturer nor the industry has offered a viable solution thus far.